/*
 * Copyright (C) 2014-2017 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include "include/JavaScriptCore/heap/CellState.h"
#include "IndexingType.h"
#include "JSTypeInfo.h"
#include "StructureIDTable.h"

namespace JSC {

    class StructureIDBlob {
        friend class LLIntOffsetsExtractor;

    public:
        StructureIDBlob() {
            u.doubleWord = 0xbbadbeef;
        }

        StructureIDBlob(StructureID structureID, IndexingType indexingTypeIncludingHistory, const TypeInfo &typeInfo) {
            u.fields.structureID = structureID;
            u.fields.indexingTypeIncludingHistory = indexingTypeIncludingHistory;
            u.fields.type = typeInfo.type();
            u.fields.inlineTypeFlags = typeInfo.inlineTypeFlags();
            u.fields.defaultCellState = CellState::DefinitelyWhite;
        }

        void operator=(const StructureIDBlob &other) { u.doubleWord = other.u.doubleWord; }

        StructureID structureID() const { return u.fields.structureID; }

        IndexingType indexingTypeIncludingHistory() const { return u.fields.indexingTypeIncludingHistory; }

        void setIndexingTypeIncludingHistory(
                IndexingType indexingTypeIncludingHistory) { u.fields.indexingTypeIncludingHistory = indexingTypeIncludingHistory; }

        JSType type() const { return u.fields.type; }

        TypeInfo::InlineTypeFlags inlineTypeFlags() const { return u.fields.inlineTypeFlags; }

        TypeInfo typeInfo(TypeInfo::OutOfLineTypeFlags outOfLineTypeFlags) const { return TypeInfo(type(), inlineTypeFlags(), outOfLineTypeFlags); }

        int32_t blobExcludingStructureID() const { return u.words.word2; }

        int64_t blob() const { return u.doubleWord; }

        static ptrdiff_t structureIDOffset() {
            return OBJECT_OFFSETOF(StructureIDBlob, u.fields.structureID);
        }

        static ptrdiff_t indexingTypeIncludingHistoryOffset() {
            return OBJECT_OFFSETOF(StructureIDBlob, u.fields.indexingTypeIncludingHistory);
        }

    private:
        union {
            struct {
                StructureID structureID;
                IndexingType indexingTypeIncludingHistory;
                JSType type;
                TypeInfo::InlineTypeFlags inlineTypeFlags;
                CellState defaultCellState;
            } fields;
            struct {
                int32_t word1;
                int32_t word2;
            } words;
            int64_t doubleWord;
        } u;
    };

} // namespace JSC
